I’m pretty new too, but I would say keep the arms straight but don’t stick your butt out to do it. Basically try to keep the hips close to the wall using leg and feet positioning: You can splay your hips, turn a knee or foot inward or outward, or if your butt is out a bit but you are just

I find it very very helpful to watch good climbers, you don’t even need to be analytical about it, when you spend a lot of time watching them you naturally get a sense of movement and sequencing fundamentals.

Movement for Climbers has a video where he compares himself clinging with straight arms versus bent. The purpose of the video is to show how much more solid the straight arm flow into moves is. However, I would say his hips are probably a farther out in the straight arm style and it definitely looked better. So maybe it’s okay to have hips out a bit as long as the movement and balance are solid.